Iran have been dominant in the continent for many years winning 10 title championships out of their 12 final matches.
In the other two matches, in 2006 and 2012, Iran ranked third.
In this year's tournament, the World No 7 won all the three matches in the group round and scored 25 goals, suffering only two goal losses.
According to Iran's coach Jesus Candelas, "It was difficult for the hosts to beat his team because of a wide gap of level between the two teams. However, the chances of winning of course depended on Vietnam."
Candelas was quoted as saying to the Tuoi Tre (Youth) newspaper that he watched Vietnam playing against Iraq and Kuwait and was impressed with the players' smooth group coordination and speed as well as agility.
Candelas believed that the teams that could prevent Iran from winning the cup this year would be defending champions Japan, first runners-up Thailand and Vietnam who always had wonderful fan following.
He noted that Vietnam has played better match after match. Iran could not lose their attention and will not be subjective.
On the host side, coach Bruno Formoso confirmed Iran's power.
He told Thanh Nien (Young People) newspaper that Iran had skillful players, who had sharpened their tactics and knew how to confuse their rivals before making them lose the match.
He added that the Vietnamese team, World No 44, had carefully watched Iran through three matches at the group round and definitely had plans to face that powerhouse.
He noted that the Vietnamese must completely control two players Hossein Tayebi and Asghar Hassanzadeh who had scored half of Iran's total goals. They also need to limit their personal mistakes that they made in the previous matches.
Formoso said that his players were confident after winning a berth in the last eight rounds, so despite mighty Iran there will be nothing impossible in football.
He said he believed that there will be a large fan following for the hosts who will play without any pressure. Vietnam beat Kuwait (2-1), so they may completely overcome Iran. It will be a 50-50 chance for the two teams.
Captain Nguyen Bao Quan said: "We are in the quarter-finals. We are playing at home with many fans encouraging every match. Iran are strong, so it is normal if we lose to them. We feel free to play this match. We will try our best to obtain good results."-VNA
